Around Day 12 after conception, the PRIMITIVE STREAK appears and the newly begun ectodermal cells form the MESODERM by blending endoderm and ectoderm. The creation of connective tissue, blood vessels, blood cells, muscles and the G.U. system is then begun as MESENCHYME, (which comes from MESODERM) emerges and becomes active. Within 21 days ECTODERM forms the NOTOCHORD at the cranial end of the PRIMITIVE STREAK. At this time the NEURAL CREST cells differentiate to begin the formation of the peripheral narrow system, the automatic nervous system and Schwann cells. At this time too, SOMITES are formed from MESODERM and they begin to line both sides of the NOTOCHORD. Eventually they will form 4244 pairs. The SOMITES continue their developmental process and soon become a lateral dermatome, a medial myotome and a ventral scleratome. This becomes in due time, the basis of the skin, muscle and skeletal elements, respectively. By week 6 after conception, the median artery [which initially supplies the hand] evolves. At this time the limb buds also develop. The upper extremity, with pronated forearms, appears first and begins to rotate externally. Within days the lower extremity appears and begins to rotate internally. By week 7 the ten finger rays appear and continue to differentiate till week 12 13 when the hands appear. During this initial 12 week period the formation of the body’s solid framework also begins. The beginning process involves MESENCHYMAL AGGREGATION into a cartilage prototype. Gradually but systematically each cartilage model becomes solid bone. This process applies to all bones except those formed through intramembranous ossification such as the skull. By week 12 the PRIMARY CENTRES of OSSIFICATION in the DIAPHYSES of most bones has appeared. Most SECONDARY CENTRES for OSSIFICATION are not present however, until after birth. The term ‘Dysplasia’ refers to the range of deformities caused by intrinsic bone disturbance. Dwarfism can be PROPORTIONATE manifesting a symmetric decrease in both truncal and limb length. Dwarfism can be DISPROPORTIONATE manifesting either a short limb disorder or a short trunk disorder. Short limbed dwarfism can affect either the proximal, the middle or the distal region of a limb. FORMS OF DYSPLASIA include: Achondroplasia Spondyloepiphyseal Dysplasia Chondrodysplasia Punctalta Kneist Syndrome AD Metaphyseal chondrodysplasia Multiple Epiphyseal Dysplasia Dysplasia Epiphysiallis Haemimeliea [known as Trevors Disease] Progressive Diaphyseal Dysplasia AD Mucopolysaccharidosis Diastrophic Dysplasia AR Cleidocranial Dysplasia AD Benign Bone Growth Dysplasia
A) Achondroplasia Achondroplasia is the most common form of disproportionate dwarfism. It is an autosomal dominant (AD) condition with an 80% spontaneous mutation. It is caused by abnormal endochondral bone formation [in the proliferative zone] and can be associated with lateinlife childbirth. It is a quantitative [not a qualitative] cartilage defect. The afflicted child will have dwarfed limbs and a normal trunk. Most will also exhibit a prominent forehead, a small nasal bridge, thoracolumbar kyphosis, excessive lordosis, trident hands, radial head subluxation plus hypotonia, during the first year of life.
Most Achondroplasia patients will have normal intelligence. They will present a normal sitting height but a standing height in the lower 3%. The motor development of each including walking will be noticeably delayed. Clinical symptoms include: posterio vertebral scalloping, delayed appearance of growth plates, short, though wide, iliac wings narrowed interpedicular distance and wedging {L1 3, T12/L1}, possible radial or tibial bowing coxa valga, genu varum and metaphyseal flaring with an inverted v shaped distal femoral physes a severely impaired growth pattern of the forearm magnum [which could cause apnea.] Surgical Options include: decompression of the spine plus bone grafting for any developing neurologic deficit.Arterial fusion with strut grafting also posteria fusion whenever there is progressive kyphosis, unaccompanied by neurologic problems. B) Spondyloepiphyseal Dysplasia This disproportionate affliction has three major forms: Congenita Form Tarda Form Pseudoachondroplastic Dysplasia [This is considered in some books to be separate]. The Congenita Form is short trunked dwarfism involving the vertebra and epiphyseal centres, AD inheritance plus clinical heterogeneity. It is not distinguishable at birth. Symptoms can include platyspondyly, scoliosis,flattened facies, odontoid hypoplasia, coxa vara and / or genu valgum. Retinal detachment and myopia are also common. The Tarda Form affects the spine and the larger joints primarily and does not manifest itself till a child is 810. The hip often becomes dislocated and premature osteoarthritis, and also scoliosis, may develop. [ Osteotomies may be useful in easing the osteoarthritis]. The Pseudoachondroplastic Dysplasia has an AD inheritance pattern and is similar to Achrondoplasia without the flattened facies. Signs and symptoms include cervical instability; scoliosis leading to lumbar lordosis, plus significant bowing of the hip, knee and elbow flexion contractures. C) Chondrodysplasia Punctata This disorder has both an autosomal recessive [AR] form and an autosomal dominant [AD] form. The AD form has variations in the severity of its symptoms but the AR rhizomelic form is almost always fatal soon after birth. The multiple punctate calcifications which cause the disorder can be clearly detected on a Radiograph.Signs and symptoms include asymmetric limb shortening, spinal deformity and also cataracts. D) Kneist Syndrome AD This disorder produces short limbed, short trunked dwarfism. The many symptoms include joint stiffness, distorted femora, scoliosis, kyphosis plus hypoplaslic pelvis and spine. Kneist Syndrome sufferers are also prone to respiratory problems, otitis media, cleft palate, myopia plus retina detachment. Radiographs are necessary to pick up early osteoporosis and also platyspondyly which is common in all sufferers.Symptomatic treatment includes constant therapy for joint contractures and ophthalmic consultation. Reconstructive procedures may also be necessary if early hip degenerative arthritis becomes severe. E) Metaphyseal Chondrodysplasia Sufferers exhibit symptoms of a group of heterogenous disorders, all characterised by the metaphyseal changes of tubular bones with normal epiphysis. McKuside This is an AR, cartilage / hair dysplasia, seen most commonly among Amish and Finnish peoples. Signs and symptoms include atlantoaxial instability and ankle deformity due to distal fibular overgrowth plus an abnormal immunologic competence. Jansen AD. This is very rare. Patients have hypercalcemia. They are quite retarded with dwarfed limbs. Their eyes are set widely apart. They have a monkey like stance. Schmid AD. Patients have coxa vara and genu varum which causes their stunted growth and bowed legs.
The disorder is hard to diagnose early as the symptoms do not become pronounced until late in childhood. Sufferers are advised to avoid obesity. F) Multiple Epiphyseal Dysplasia This is a disproportionate form of dwarfism which does not manifest symptoms until a child is school aged, sometimes in his/her teens.It is characterised by delayed and/or irregular ossification at multiple epiphyseal. There are two forms: Ribbing which is mild Fairbank which is much more severe. Clinical Problems Include very short, stunted metacarpals/metatarsals, abnormal ossification, T12/L1 notching and deformed ring apophysis, irregular femora, valgus knees [osteotomies may help],waddling gait, early arthritis of the hip. G) Dysplasia Epiphysealis Hemimelica [Commonly known as Trevors Disease] This disorder affects only one limb and only one half of this limb.Sufferers develop an osteochondroma.[This is a benign tumour made up of a stalk of bone capped with cartilage.] It manifests itself in late childhood and develops into an irregular shaped enlargement of half of the epiphyses usually the medial half. It most commonly affects the knee joint. Large osteochondromas can interfere with skeletal growth causing deformity. In some instances they are relatively problem free. Partial excision of the overgrowth, if large is required. H) Progressive Diaphyseal Dysplasia AD Sufferers develop symmetric, cortical thickening of one or more of the larger bones such as the tibia, femur or humerus. Only the diaphyseal portion of the bone is affected. The attached muscle is subsequently weakened so walking is delayed in infants whose leg bones are affected. Progressive symptoms include scoliosis, possible limb length inequality plus increasing difficult of movement. I) Mucopolysaccharidosis This form of dwarfism which is proportionate is caused when a hydrolase enzyme deficiency creates an accumulation of mucopolysaccharides [MPSs]. It is easily diagnosed due to the amount of complex sugars which appear in the urine. There are four main types. Hurler Syndrome Hunter Syndrome Sanfilippo Syndrome Morquio Syndrome. [This is the most common. It manifests itself when the patient is about 18 months old.] Signs and Symptoms include: knock knees, a waddling gait, thoracic kyphosis, coxa vara with non ossified femoral heads, anterior beaking of vertebrae, thickened skull bullet shaped metacarpals, C1/C2 instability [due to odontoid hypoplasia] which requires decompression and also cervical fusion. J) Diastrophic Dysplasia AR This is a very severe, short limbed form of dwarfism.It is associated with a disorder of type II. Collagenin the physis. The patients body takes on a twisted appearance. Other signs and symptoms include painful joint contractures, rigid club feet, mid thoracic kyphoscoliosis, cervical kyphosis [which requires neurologic sequela treatment] a cleft palate, spina bifida occulta, thoracholumbar kyphoscoliosis, cauliflower cars and atlantoaxial instability due to odontoid hypoplasia. K) Cleidocranial Dysplasia AD This is a proportionate form of dwarfism which affects only those bones which are formed intramembranously. Patients suffer delayed skull suture closure, frontal bossing , coxa vara [an intertrochanteric osteotomy could be considered if varus is <100 degrees] wormain bone formations and delayed ossification of the pubis.
The growth of the afflicted child is stunted and he/she will have aplasia of part or all of the clavical. Often the lateral part of the clavicle will be missing. L) Benign Bone Growth Dysplasias These disorders fall into the major categories. Hereditary Exostosis [An outgrowth of bone, usually the femur or tibia] Maffueci Syndrome Ollie's Disease There are seven major disorders listed in this category. A brief description of each is given in the ensuing text: Down Syndrome (Trisomy 21) This is the most common chromosomal abnormality. There is a higher incidence among ‘lateinlife babies. The afflicted children usually manifest ligament laxity, hypotonia, endocrine disorders, premature ageing, mental impairment to varying degrees and an inclination towards heart disease. Orthopaedic problems include: spinal disorders such as scoliosis and spondylolisthis hip instability may need an osteotomy. patellar dislocation planovalgus feet metatarsus primus varus slipped capital femoral epiphysis If surgery is planned preoperative cardiac evaluation is essential.
Turner Syndrome D) Turner Syndrome 45, XO affecting females. Afflicted girls exhibit some or all of the following symptoms. short stature cubitus valgus web neck sexual infantilism scoliosis [which can be exacerbated to some degree with hormonal therapy] renal anomalies [affecting about 2/3 of patients] cardiac anomalies [affecting about 1/3 of patients] genu valgum Malignant hyperthermia is common after anaesthetic use
Noonan Syndrome Affecting males.
Boys suffering this disorder differ from the Turner Syndrome girls in that they have normal sexual genotypes. Other symptoms are similar including a high risk of malignant hyperthermia if anaesthetics are used. PraderWilli Syndrome This is a chromosomal abnormality. Afflicted children are hypotonic and intellectually impaired. They develop a ‘floppy’ appearance and gait and tend towards obesity. They will suffer one or more of the following symptoms growth retardation hypoplastic genitalia scoliosis hip dysplasia insatiable appetite
Menke’s Syndrome This is an xlinked recessive disorder of copper transport. It affects bone growth and causes an unusual crinkly hair condition. It differs from Occipital Horn Syndrome [which also affects copper transport] in that there are no boney outcrops from the occiput of the skull.
. Rett Syndrome Females This disorder is characterised by progressive impairment and stereotaxic abnormal hand movements. It does not manifest until a child is 6 to 18 months of age at which stage they exhibit symptoms similar to cerebral palsy. Most will later develop scoliosis with a c shaped curve which is unresponsive to bracing. Spasticity causes joint contractures which are treated as in cerebral palsy. Teratogens Disorders have been presented in three separate categories. Material Diabetes This can lead to sacral agenesis and anancephaly, also heart defects. Foetal Alcohol Syndrome Maternal alcoholism can cause many growth disturbances including:
CNS dysfunction hip dislocation Cspine vertebral and upper extremity fusions dystrophic facies congenital scoliosis myelodysplasia Others Unborn children can suffer orthopaedic disorders due to: drugs such as thalidomide, aminopterin, phenytoin trace metals maternal conditions associated with infection and intrauterine factors. Haemophilia Patients suffer severe bleeding episodes plus skeletal / joint sequelae. It is a sexlinked recessive [XR] disorder with three faces: decreased factor VIII [Haemophilia A] abnormal factor VIII with platelet dysfunction [von Willebrand’s disease] factor IX [Haemophilia B known as Christmas Disease]
It can be mild [525% of factor present], moderate [15% of factor present], or marked [1% of factor present]. Haemarthrosis results in painful swelling and severe difficulty in movement of affected joints. Deep intra muscular bleeding is common. This can lead to the formation of a blood cyst (pseudotumour) in soft tissue or bone.
Radiographic findings in haemophilia include: epiphyseal overgrowth with leg length discrepancy generalised osteoporosis with resultant fractures squaring of the patellas and condyles cartilage atrophy due to enzymatic matrix degeneration
Therapy includes fracture management, open synovectomy, arthroscopic synovectomy, contacture release, osteotomies, radiation synovectomy and total joint anthroplasty. Overall treatment of haemophilia has become more complex as the risk of HIV transmission in factor VIII replacement, has increased. Prior to screening almost all haemophiliacs became H.I.V. positive. Antibody inhibitors are present in 20% of haemophiliacs and are a relative contraindication to surgery. Large levels of factor VIII are required to offset the inhibitors. Leukemia
This is the most common malignancy of childhood. It is caused by septic arthritic lesions [occasionally lytic] or demineralisation of bones. About 1/3 of afflicted children develop musculoskeletal complaints usually of the back, pelvis and legs. Management includes chemotherapy. Sickle Cell Anaemia Sickle Cell disease usually manifests when the afflicted child is aged 23 years. It usually leads to bone infarctions. The symptoms include: osteonecrosis of femoral and humeral heads growth retardation because of skeletal immaturity. an inclination to salmonella dactyulitis [hand and foot swelling] septic arthritis osteoporosis and cortical thinning
Preoperative oxygenation and exchange transfusion are helpful for sufferers who require surgery. Hydroxyurea has produced dramatic pain relief for bone crises.
Gaucher’s Disease also known as Familial Splenic Anaemia. It is an aberrant AR lysosomal storage disease. It is characterised by an accumulation of cerebroside in cells of the reticuloendothelial system. Sufferers exhibit some or all of the listed symptoms: metaphyseal enlargement femoral head necrosis osteopenia moth eaten trabeculae ‘Erlenmeyer flask’ distal femora possible sclerosis occasional ‘Bone Crisis’ as in Sickle Cell Anaemia. bleeding abnormalities The disease is most commonly seen in children of Jewish descent.
Niemann Pick Disease This disorder is caused by an accumulation of phospholipid in RES cells. It is most common in children of European Jewish descent. It is characterised by marrow expansion and cortical thinning in the long bones plus coxa valga. Thalassemia It is most common in children of Mediterranean descent. Symptoms are similar to some in Sickle Cell Disease including severe bone pain. Leg ulceration is common. Radiographs are needed to pick up developing osteoporosis and distorted trabeculae.
Acquired Immunodeficiency Syndrome [AIDS] The incidence of children born with AIDS has increased dramatically. Afflicted children require ongoing medical support. Protection for surgeons is essential. Nine major metabolic /arthritides disorders are presented. A brief description of each is presented in ensuing texts. Infantile Cortical Hyperostosis This condition is benign and self limiting. It manifests before a child is 9 months old presenting soft tissue swelling and bony cortical thickening especially of the jaw and ulna. There is always a periosteal reaction. A similar disorder occurs in older children, with hypervitaminosis A. Infantile Cortical Hyperostosis does not however produce bleeding gums, fissures at the corners of the mouth or the liver abnormalities associated with the disorder suffered by older children. Older children are also likely to suffer scurvy and progressive diaphyseal dysplasia. Osteogenesis Imperfecta Ol. This disorder presents a decreased collagen secretion. Common symptoms include: brittle ‘wormaian’ bones scoliosis short stature ligamentous laxity tooth defects hearing defects
The disorder is ongoing displaying differing inheritance patterns and severity. Classification of use is that of Sillence (Type I, AD, blue sclerae, tarda teeth ± involved A or B; type II, AR, blue sclerae, lethal; type III, AR normal sclerae, birth fractures, short, progressive; type IV, AD, normal sclerae, mild form) The clinical Factors include: thin cortiees fractures [the bones do not remodel] spinal deformities including scoliosis
Symptomatic management includes early bracing and sofield osteotomies using either fixed length Rush rods or telescoping intramedullary rods.
Rickets This disorder is caused when the mineralisation at the epiphyses of long bones is affected by lack of calcium; and sometimes phosphorus. Severe cases are characterised by:
brittle bones with physeal widening bowing of long bones ligamentous laxity enlargement of costal cartilages dorsal kyphosis transverse radiolucent lines flattening of the skull (platyspondyl) gross distortion of the maturation zone at the growth plate a poorly defined zone of provisional calcification. ‘swiss cheese’ trabeculae
There are several varieties of rickets based on the base cause which could be poor diet, G.I., kidney or endorgan dysfunction. See adult classification.
Idiopathic Juvenile Osteoporosis This is a rare, self limited disorder. It manifests in an afflicted child at around 8 12 years of age. The first signs include bone and joint pain, growth arrest and osteopenia. Unlike Rickets, calcium and phosphorus levels are normal. Spontaneous resolution usually occurs 2 4 years after the onset of puberty. Osteopetrosis This disorder is the result of a thymus defect which causes the failure of osteoclastic and chondroclastic resorption. The clinical factors include:
dense bone / marble bone ‘Erlenmyer flask’ proximal humerus / distal femur ‘rugger jersey’ spine
There is a mild form AD. There is a more serious malignant form AR. Bone marrow transplants may be helpful in treating the malignancy.
Juvenile Rheumatoid Arthritis / Juvenile Chronic Arthritis This is a persistent, noninfectious disease which is usually diagnosed if the symptoms last more than 6 weeks after other etiologies have been ruled out. The symptoms include: a rash iridocyclitis pericarditis presence of rheumatoid factor intermittent fever
morning stiffness C. spine involvement tenosynovitis Juvenile Rheumatoid Arthritis affects more girls than boys. The wrists, hands, spine, hips, knees, ankles and feet can all be seriously affected. In 50% of cases the patients’ symptoms resolve with sequelae usage. In 25% of cases the patients remain slightly disabled. In 25% of cases the patients suffer ongoing crippling arthritis and also blindness. Arthrodesis and Arthroplasty may be required for severe J.R.A. Slitlamp examination is necessary twice yearly as progressive iridocyclitis can lead to blindness if left untreated.
Connective Tissue Syndrome This disease presents a wide spectrum of features. They have been grouped; to form three separate sections. 1) Marfan Syndrome This is an AD disorder of collagen synthesis. It is characterised by: arachnodactyly pectus deformities cardiac deformities scoliosis ‘sedia’ finders
It can also include dural ectasia and meningocele.
2) Ehlers Danlos Syndrome This is an AD disorder. It is characterised by: ‘cigarette paper’ skin soft tissue / bone fragility soft tissue calcification joint hypermobility dislocation on occasion, vascular and visceral tears
3) Homocystinuria This is the result of an AR inborn error of methionine metabolism. It is characterised by: osteoporosis inferiod lens dislocation a marfanloid like habitus with suffering joints.
Mental retardation is common with this disorder. Early treatment with Vitamin B6 and a decreased methionine diet is sometimes successful.
Acute Rheumatic Fever This is an auto immune process which affects children in the 5 15 age bracket. It manifests a few weeks after a streptococcal infection. It is characterised by: erythema marginatum [ a pink rash on trunk & extremities, not the face]. migratory arthritis fever subcutaneous nodules carditis TreatBRACHIAL PLEXUS PALSY Better obstetric management has led to a decrease in severity of Brachial Plexus Palsy but there are still two babies affected in each 1000, born. Stretching or tearing of the brachial plexus occurs usually because of a forcep delivery, a larger than average baby, a breach birth, shoulder dystocia or prolonged labour. The ErbDuchenne (C5,6) type affecting the elbow wrist or hand is the least disturbing. The Klumpke (C8,T1) type presents a worse prognosis than the above. The Total Plexus condition is the most disturbing of all. In 90% of cases the problem resolves without surgical intervention. Surgery would be indicated however, if there’s a lack of bicep function, 3 months after the injury. The surgical options include Latissimus and teres major transfer to the shoulder external rotators, proximal humerus rotational osteotomy, tendon transfers for elbow flexion, releasing contractures or microsurgical nerve grafting. TORTICOLLIS This deformity is associated with hip dysplasia and metatarsus adductus, resulting from contracture of the sternocleidomastoid muscle. Obvious symptoms may include: ophthalmologic disorders which cause the child to tilt his/her head to see. posterior fossa brain tumours. Cspine anomalies The etiology remains uncertain but studies suggest that it is caused by an intrauterine Compartment Syndrome. Fibrosis of the muscle plus a palpable mass [which appear within 4 weeks] are usually the first signs. The muscles of
most affected children respond to ongoing, passive stretching within the first year. If the problem persists surgical release of the muscle distally [or proximally and distally] may be required. CONGENITAL PSEUDOARTHROSIS OF THE CLAVICLE This disorder involves the middle third of the clavicle. It does not have an associated fracture callus and almost always occurs on the right side. Surgical repair is needed if the child suffers severe pain. ment includes salicylates and appropriate antibiotics. Cerebral Palsy is the result of injury to the immature brain. It is a non progressive neuromuscular disorder. Etiology includes perinatal infections and prenatal intrauterine factors. The disease results in a mixture of muscle weakness and spasticity. Cerebral Palsy can be classified according to the placement of the disorder [topography] or the particular movement disorder [physiology]. Topographic Classification includes: Diplegia affecting the lower extremity. (Most sufferers eventually walk. IQ is unaffected. Strabismus is common.) Hemiplegia affecting both the upper and lower extremities on one side, with spasticity. (The sufferers will eventually walk.) Total Involvement with a high mortality rate. [Sufferers are usually unable to walk. IQ. is low] Physiologic Classification includes: athetosis which presents a constant succession of slow, writhing involuntary movements, [It is difficult to treat]. ataxia with the affected child unable to coordinate his/her muscles for voluntary movement, resulting in an unbalanced gait. spasticity exhibiting increased muscle tone and hyperreflexia resulting in slow restricted movements. mixed involving a combination of spasticity and athetosis with whole body involvement.
An Orthopaedic Assessment is based on thorough birth and developmental history taking. A patients locomotor profile is based on the persistence of primitive reflexes. (The presence of two or more usually means the child will be a nonambulator). Surgery is commonly performed on patients who have no potential for walking on independence. The purpose is to : avoid painful arthritis by keeping the hips located. maintain a sitting posture maintain spinal stability The use of a toxin (intramuscular botulinum toxin) to temporarily reduce dynamic spasticity is helpful though still experimental. It is thought that its use promotes normal muscle growth and avoids the development of soft tissue contractures. The treatment most used for spastic C.P. involves the surgical resection of the dorsal rootlets not exhibiting a myographic or clinical response to stimulation. It requires multilevel laminectomy or laminoplasty. Specific Disorders include: Gait Disorders These are the most common. The use of three dimensional computerised gait analysis [with dynamic E.M.G] plus force plate studies permit more effectiveness preoperative decision making and also post operative analysis. Specific abnormalities involving abnormal gait of the knee can be classified as Jump Knee: Cronch Knee: Stiff Knee: Recurvatum Knee. Specific procedures have been devised to treat each as required. Other surgical options for gait disorders include: hip adduction adduction release knee flexion hamstring lengthening knee hypertension rectus femortics lengthening talipes valgus peroneal lengthening / grice subtalar fusion hip flexion psoas tenotomy or recession stiff leg gait distal rectus transfer to hamstring spastic hip adductor release talipes varus split anterior or posterior tibialis transfer hallux vagus osteotomy / MTP fusion Surgery is usually performed in the 45 year age group. Spinal Disorders Spinal disorders usually involves scoliosis and tends to make wheel chair occupation difficult. Two types occur: Group1. double curves with thoracic andlumbar components andlittle pelvic obliquity Group 2. larger lumbar or thoracolumbar curves with marked pelvic obliquity. Custom moulded seat inserts will allow better positioning and comfort but will not prevent further curve progression. Orthopaedic surgery varies according to the disorder: group 1. curves in ambulators are treated with posterior fusion only.
group 1. curves in sitters, plus group 2. curves, require both anterior and posterior fusion with luque rods and sublaminar wires together with pelvic fixation including the Galveston technique and unit rod variation. Hip Subluxation / Dislocation The goal is to keep the hip reduced avoiding painful arthritis. Femoral or acetabular osteotomies may be required to maintain this stability . This disorder prevents 4 separate stages. 1. Hip at Risk.Hip May require surgery before age 3. Affirmed by abduction of <45 degrees with partial uncovering of the normal head on radiographs. May need abductor and psoas release. 2. Hip Subluxation Femoral or pelvic osteotomies may be considered but for children with abduction of <20 degrees it is best treated with adductor tenotomy, sometimes with psoas release/recession. 3. Spastic Dislocation The type of pelvic osteotomy most suited is determined by three dimensional C.T. scans to show the area of acetabular deficiency and the congruency of the joint surfaces. A Shanz abduction osteotomy may be required for a late dislocation with a Girdlestone resection arthroplasty performed in severe cases.
4. Windswept Hips This is characterised by the abduction of one hip plus the adduction contracture of the contralateral hip. Bracing or tenotomies may abduct the abducted hip while releasing the adducted contracture of the other Hand Abnormalities See separate section on Disorders of the Hand. Knee Abnormalities The most common problems include flexion contractures and decreased range of motion. Hamstring lengthening is sometimes helpful but the best results have come from distal transfer of an outofphase rectus femoris muscle to semitendinosis or gracilis. Foot and Ankle Abnormalities These are common in cerebral Palsy sufferers. E.M.G. evaluation is helpful in defining the specific problem, which includes: 1.Equinovalgus Foot which is caused by spastic peroneals, ligamentous laxity and contracted heel cards. [It is most common in spastic diplegia patients.] Peroneus brevis lengthening is used to correct moderate valgus. Medial sliding calcaneal osteotomy can be used in more serious cases. 2.Equinovarus Foot which is caused by overpull of the posterior or anterior tibialis tendons sometimes both. Split muscle transfers have proven to be the most effective if the afflicted muscle is spastic during both stance and swing
phases of gait. The split posterior tibialis transfer is effective in those cases which exhibit spasticity of the muscles, weak peroneals and flexible varus foot. Most recently combined splits anterior tibial tendon transfer has been used with intramuscular lengthening of the tibial tendon for dynamic varus of the hindfoot and
HEREDITARY NEUROPATHIES The Hereditary Neuropathies category includes all disorders associated with multiple G.N.S. lesions Friedreich’s Ataxia This involves motor and sensory defects. It is a spinocerebellar degenerative disease with manifests before age 10. The symptoms include nystagmus, casus foot, cardiomyopathy, scoliosis and a distinct change in gait. Charcot Marie Tooth Disease [Peroneal Muscular Atrophy] There are two forms, one manifesting during teenage years [a hypertrophic form] and a neuronal form manifesting in later life. Patients suffering the hypertrophic form exhibit peroneal weakness, hammer toes causing corns and callouses, pes cavus and stork legs. Treatment includes plantar release triple arthrodesis versus calcaneal, posterior tibial tendon transfer and possibly, metatarsal osteotomies. This form involves motor defects much more than sensory defects Dejerine Sottas Disease AR. This is a hypertrophic neuropathy of infancy [CMT3]. Spinal deformities are common [degenerating to wheelchair condition by 3rd decade] plus pes cavus foot, delayed ambulation and stocking glove dysesthesia. Riley Day Syndrome [Dysautonomia] This is the main one of five inherited [AR] sensory/autonomic neuropathies. It is found only in children of Ashkenazic Jewish descent. Sufferers exhibit frequent sweating alacrima, postural hypotension and sensory loss, pneumonia, plus dysphagia.
MYELODYSPLASIA [Spina Bifida] Spina Bifida is the result of a disorder of the spinal cord development /closure or a secondary rupture of the developing cord secondary to hydrocephalus. Patients suffer muscle imbalance, possible hip dislocations due to intrauterine, positioning, club feet and knee hyperextension. Fractures [particularly of the hip and knee] are also common. If the afflicted child has tethered cord, hydrocephalus or hydromyelin, he/she will suffer a rapid increase of scoliotic curvature, new neruologic deficit, also spasticity. Principles of Overall Treatment
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careful, ongoing observation/assessment of the patient and the effect of each recognised milestone of the disease.
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proper use of orthotics.
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surgery [if necessary] to focus on balancing of muscles and correction of deformities.
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provision of a latex free environment if surgical procedures are performed.
Hip Disorders
Those caused by flexion contractures occur in patients with thoracic/high lumbar myelomeningocele or in patients who are sitters. Treatment for these patients consists of anterior hip release with tenotomy of the iliopsoas, sartorius, rectus femoris and tensor fascia lata. Hip abduction contracture resulting in pelvic obliquity plus scoliosis, can be treated with the OberYount procedure. If adduction contractures are manifest than adductor myotomy is required. hip dislocation occurs [most common at the L3/L4 level] surgery is needed to maintain the range of motion and achieve full hip extension [containment is a secondary concern]. Treatment of hip dislocation varies. If L2 or higher the hips need to be left symmetric, if L4 or lower, the dislocation needs to be reduced. If there is neurologic decompensation [indicated by dislocation of the low lumbar level] the tethered cord must be released prior to reducing the hip. Ankle and Foot Deformities Most have valgus foot. If so clubfoot release, tendon release plus posterior tibialis lengthening may be necessary. Ankle valgus is treated with tibial osteotomy or Archillles tendon tenodesis to the fibula. Rigid clubfoot is common in L4 level patients. This requires complete subtalar release via a transverse incision, lengthening of tibialis posterior and Achilles tendons plus transfer of tibialis anterior tendon to the dorsal midfoot. Secondary hindfoot valgus requires a medial displacement calcaneal sliding osteotomy. Knee Problems These are usually associated with quadriceps weakness which can be treated with hamstring release. [not needed if the patient is unable to walk]. If recurvatum [caused by club feet and/or hip dislocation] becomes a problem it can be treated with serial casting and K.A.F.Os. Valgus deformities sometimes require iliotibial band release or late osteotomies Spine Problems Upper lumbar kyphosis and other congenital malformation, result from disorders of the spine due to lack of segmentation or formation. Kyphosis is a difficult problem The Lindseth Procedure involving resection of the kyphosis with local fusion is the most common treatment. Scoliosis [Resulting from the muscle imbalance of thoracic level paraplegia] is often severe and progressive. If curves are 60 degrees the most effective treatment appears to be segmental luque sublaminar wiring with fixation to the pelvis or the front of the sacrum usually preceded by anterior release and fusion. Infection is a problem due to frequent septicemia in patients and poor skin quality. Pelvic Obliquity This is caused by prolonged unilateral hip contractures or scoliosis. It is relieved by custom seat cushions, and surgery, including spinal fusion, thoracolumbosacral orthosis or in more severe cases, pelvis osteotomies.
MYOPATHIES [Muscular Dystrophies] These disorders are progressive involving muscle weakness. It is a noninflammatory, inherited disorder with several, separate classifications.
These include: Duchenne This affects young boys only. The first symptoms are decreased motal skills, clumsy walking, calf pseudohypertrophy, definite Gowers sign, lumbar lordosis. Clinical investigations will show an absent dystrophia protein on muscle biopsy DNA testing and a markedly elevated C.P.K. Hip extensions are often the first muscle group affected. Afflicted boys lose independent ambulation by age 10; are wheelchair bound by age 14, and become bedridden by age 16, owing to the resultant spinal deformity. Cardiorespiratory complications are frequent and patients usually die before age 20. Beckus Dystrophy is similar but these patients tend to live longer. Fascioscapulohumeral AD Disorder This affects people between 640 years of age. It is characterised by a winging of the scapular which can be stabilised by scapulothoracic fusion. Facial muscle abnormalities also occur sometimes upper arm muscles disturbance as well, though C.P.K. remains normal. It is inherited in an autosomal dominant pattern. Others These include Gowers, involving distal disorders, with a high incidence in Sweden, also ocular, oculopharyngeal with a high incidence in French Canadians.
MYOTONIC MYOPATHIES This category includes A.D. disorders presenting the inability of muscles to relax after contractures. These are three basic types: 1. Dystrophic Myotonia [Steinert’s] caused by a defect in chromosome 19. Other features include distal/lower extremity involvement, ‘dive bomber’ E.M.G., small gonads, low IQ and heart disease. 2. Paramyotonia Congenita [Eulenburg’s] caused by a defect in chromosome 17 skeletal sodium channel. The symptoms become apparent with exposure to cold, especially in the hands. Quinine or mexiletine are sometimes helpful. 3. Myatonia Congenita [Thompson’s] caused by a defect localised to chromosome 7 region of human skeletal muscle chloride channel. Patient’s exhibit widespread involvement with increased hypertrophy though little weakness. The symptoms improve with exercise.
CONGENITAL MYOPATHIES These are non progressive disorders which cause ‘floppy baby’ syndrome. Hypotonia in infants, usually affects the pelvic and shoulder girdles. In such cases a Muscle Biopsy Hitochemical analysis is required to ascertain the specific problem/cause.
ARTHROGRYPOTIC SYNDROMES
There are four major forms. 1.Arthrogryposis Multiplex Congenita [Amyoplasia] This is a non progressive disorder with multiple, congenitally rigid joints. It is caused by any of several conditions which limit foetal movement and can be neuropathic, myopathic or mixed. It resembles polio in that sensory function is maintained while motor function is lost. Upper extremity involvement usually includes adduction and internal rotation of the humerus, wrist flexion and elbow extension plus ulnar deviation. Treatment consists of passive stretching in the early stages with osteotomies, if needed, after 4 years of age. Lower extremity involvement often includes rigid club feet, knee contractures and hip dislocation. The spine in some cases reveals C shaped scoliosis and fractures are common. Treatment includes soft tissue releases, open reduction of hip dislocations, surgical treatment for club feet [after an attempt at posteromedia release] plus an attempt at achieving ambulation. 2. Larsen Syndrome This is similar to Arthrogryposis in clinical appearance but the joints are less rigid. It is characterised by multiple joint dislocations, cervical kyphosis, flattened facies and scoliosis. 3. Multiple Pterygium Syndrome This is an A.R. disorder characterised by scoliosis, cutaneous flexor surface webs, and congenital vertical talus. 4.Distal Arthrogryposis Syndrome This is an A.D. disorder which, in most cases, affects the hands [presenting ulnarly deviated fingers, adducted thumbs with web space thickening plus M.C.P. and P.I.P. flexion contractures] or the feet [with vertical talus and club feet being common].
POLYMYOSITIS [Dermatomyositis] This is a predominantly female disorder. It is a febrile illness and can be acute or insidious. Sufferers exhibit photosensitivity plus increased C.P.K. and E.S.R. values. They present muscles which are tender, and indurated. Biopsies reveal a pathognomonic inflammatory response.
MYASTHENIA GRAVIS This is a rare, A.D. disorder in which, for reasons not known, the body’s immune system attacks and gradually destroys the receptors in muscles that are responsible for picking up nerve impulses. The muscles, consequently become weak and fine easily. The eyes, face, throat and limb muscles are most commonly affected. Sufferers usually exhibit drooping eyelids, a blank facial expression plus weak, hesitant speech. It affects more women than men. Treatment consists of antiacetyl/cholinesterase agents Cyclosporin or a thymectomy, if the problem is caused by a dysfunctioning thymus gland.
ANTERIOR HORN CELL DISORDERS There are two specific forms. Poliomyelitis
A viral infection which, at its worst destroys the anterior hom cells in the spinal cord and brain stem motor nuclei, causing paralysis. The disease can be mild, severely disabling, or fatal. It has almost completely disappeared from the developed countries since vaccination began in the 1950’s. A feature of polio is that normal sensation accompanies the muscle weakness. Spinal Muscle Atrophy This is an A.R. disorder involving destruction of anterior hom cells from the spinal cord. It is more common in girls than boys. There are two forms. Werdbug Hoffman form which is present at birth giving the sufferer a very limited life span. Kugelberg Wellander form which develops later in life and is not as severe. Spinal Muscles Atrophy is characterised by progressive scoliosis. Treatment is similar to Duchenne Muscular Dytrophy except that fusion may be needed earlier. Patients exhibit symmetric paresis. The lower extremity and proximal muscles being the most commonly involved.
ACUTE IDIOPATHIC POSTINFECTIOUS POLYNEUROPATHY [Guillain Barr Syndrome] This is a rare disease caused by demyelisation following a viral infection. Patients suffer symmetric ascending motor paresis. C.S.F. protein is usually elevated. The disease is usually selflimited.
OVERGROWTH SYNDROMES There are three major forms. 1. Hemihypertrophy This disease is often associated with renal abnormalities [most often Wilms’ Tumour]. The most commonly known cause is neurofibromatosis but it can be caused by any of several separate syndromes, most of them idiopathic.Treatment of the symptomatic leglength discrepancy is discussed within the Paediatric Spine Disorders Section. 2. Proteus Syndrome This is a rare, bizarre disorder resulting in overgrowth of the hands and feet, genu valum, haemangioma, scoliosis, complete facial disfigurement, lipomas and nevi. 3. Klippel Trenaunay Syndrome This disturbing disorder is associated with cutaneous haemangioma plus varicosities. The subsequent overgrowth is caused by underlying A.V. malformations. If hypertrophy of the extremities is severe, amputation may be necessary.
PAEDIATRIC SPINAL DISORDERS
There are many variations. These have been divided and grouped into eight separate categories as shown below:
IDIOPATHIC SCOLIOSIS This manifests as a lateral deviation and rotation of the spine with no identifiable
cause, but it is usually related to a brain stem, hormonal or proprioception disorder. The adolescent form is most common but there is an Infantific form also a Juvenile form. Right thoracic curves, with apex T7 or T8 are the most common, followed by double major, left lumbar and right lumbar, in that order. Severe curves [>90 degrees] accompanied by cardiopulmonary dysfunction result in extreme pain and early death. Afflicted children are first noticed because of a trunk shift, shoulder or pelvic asymmetry, asymmetric umbilical reflex, spinal curvature, asymmetric rib hump and/or limb length inequality. Inclusion of the iliac crest on radiographs will reveal the degree of skeletal maturity. A lateral radiograph to check for spondylolisthesis is also recommended. An M.R.I. scan is needed if there is excessive Kyphosis, rapid progression, neurologic symptoms, onset before 11 years, of left thoracic/thoracolumbar curves. Treatment includes careful observation, some for bracing and if needed surgery. Bracing does not rectify the problem but does halt rapid progression. Surgical options include instrumentation without fusion for Infantile, also Juvenile forms. There are several options for the Adolescent form but posterior fusion and instrumentation with Harrington distraction rods are the most common. In all forms of surgery for idiopathic scoliosis, great care must be taken to choose the most appropriate/effective fusion level. It varies according to the age of the child, the degree of the curve and also the degree of progression. Surgical complications include pseudoarthrosis, implant failure [due to early hook cut out and late rod breakage] also infection of the wound, and the appearance of a neurologic deficit that was not apparent preoperatively. Points To Note Re. Infantile Scoliosis: •
male predominance
•
manifests between 2 months and 3 years
•
is accompanied by a flattening of the skull and other congenital defects
Points To Note Re. Juvenile Scoliosis •
similar to adolescent scoliosis in terms of symptoms and treatment
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manifests between 3 years and 10 years
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curve progression is a high risk [70% require treatment, 50% require bracing
and 50% require surgery.
•
fusion needs to be delayed until adolescence.
CONGENITAL SPINE DISORDERS Congenital spinal disorders are due to a development defect in the mesenchymal anlage during the 4th to 6th week of gestation. Three basic defect types are noted: •
failure of formation
•
segmentation
•
mixed
There are two separate disorders: Congenital Kyphosis in which a failure in formation Type I gives the worst prognosis for progression and neurological involvement. It is also the most likely to result in paraplegia and requires surgery. Posterior fusion is the most effective in children under 5 years with curves less than 50 degrees. Combined anterior/posterior fusion is more suitable for older children or those with more severe curvature. Type II. congenital kyphosis is not usually as serious as Type I.but posterior fusing is needed if the curving is progressive.
Congenital Scoliosis This is the most common congenital spinal disorder. The best prognosis is a block vertebrae caused by a failure of segmentation. The worst prognosis presents a unilateral unsegmented bar with a contralateral fully segmented hemivertebra, which will require surgery [the deformities do not require surgery unless progression [which isn’t usual] becomes obvious]. Posterior fusion either with or without instrumentation is the most common treatment for progressive curves. If the ‘crankshaft’ phenomenon occurs however [due to continued anterior spinal growth] the anterior/posterior fusion may be required.
NEUROFIBROMATOSIS This is an A.D. disorder associated with neoplasia and skeletal abnormalities. It is of neural crest origin and is characterised by numerous neurofibromas [soft fibrous swellings that grow from a nerve] and cafeaulait spots. It is an uncommon, inherited disease. It manifests in its most serious form bone abnormalities . The spine is the most common site and may reveal vertebral scalloping, enlarged foramina, severe
apical rotation, pencilling of transverse processes or ribs, a paraspinal mass and/or short, light curves. Surgical treatment involves posterior fusion with instrumentation if there is less than 50 degrees kyphosis. Anterior fusion and strut grafting combined with posterior fusion and instrumentation is required if there is more serious kyphosis. Neurologic involvement is the most common complication of neurofibromatosis. This can be caused by aspects of the deformity itself, by a soft tissue mass, an intraspinal tumour or by dural ectasia. Anterior decompression with strut grafting followed by posterior fusion is required if this happens.
KYPHOSIS There are four major types: Congenital Kyphosis [information given under the Congenital Spine Disorders section] Scheuermann’s Disease This is characterised by increased thoracic kyphosis [more than 45 degrees] with more than 5 degrees anterior wedging at three sequential vertebrae. Other clinical symptoms include:
•
end plate irregularitie
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spondylolysis [2050%]
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Schmorl’s nodes
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disc narrowing
It is more common in males and usually manifests in adolescence. Treatment involves bracing [if the curve is progressive] before skeletal growth is completed. If surgical correction is needed [for an adult with more than 65% curve] it usually involves anterior release and interbody fusion followed by posterior fusion with dual rod segmentally attached, compression instrumentation. Lumbar Scheuermann’s disease is less common than the thoracic variety and usually less severe as there is no vertebral wedging, though irregular end plates, decreased disc height and Schmorl’s nodes are evident. Postural Round Back This disorder is similar to other forms of Kyphosis but there are no vertebral body changes and no sharp angulation. Correction of the problem usually involves backward bending and prone hyperextension. Sometimes bracing is required. Surgery is rare. Others
Kyphosis can be caused by infections, various bone Dysplasias [including Kneist syndrome] neoplasms, spondylitis or trauma. Post laminectomy kyphosis can be sufficiently severe to require early anterior and posterior fusion.
NEUROMUSCULAR SCOLIOSIS Many children with neuromuscular disorders develop some form of spinal abnormality; scoliosis being the most common. The curving differs from the curves of idiopathic scoliosis in several ways including: •
they involve more vertebrae
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are less likely to have compensatory curves
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they progress more rapidly and often continue after maturity
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they may be associated with other bone deformity, cervical involvement and pelvic obliquity
•
there is decreased pulmonary function plus pneumonia and/or atelectasis
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wheelchair bound patients may become bedridden
Orthotic use is advised until age 12 when corrective fusion is required to provide permanent stability. Children with upper motor neuron disease are usually treated with a body jacket or seat. Orthotics but eventually require fusion if there’s a curve progression of >50 degrees. Children whose affliction is severe may require both anterior and posterior procedures.
LOW BACK PAIN Acute, persistent back pain in children should always be investigated. It can be associated with osteomyelitis or diskits. Other, probable disorders, include:
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sciatica [herniated nucleus pulposus]. This may require surgical intervention.
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spondylolysis which can result from sports injuries
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a tumour such as osteoid osteoma.
•
a spinal cord anomaly
Bone scans are the best method of screening and diagnosing a possible serious cause of back pain.
CERVICAL SPINE DISORDERS
There are many disorders in this category including: KlippelFeil Syndrome Atlantoaxial Instability Os Odontoideum Pseudosubluxation of the Cervical Spine Intervertebral Disc Calcification Syndrome Basilar Impression/Invagination Information concerning each disorder is given, as listed, in the ensuing text. 1) KlippelFeil Syndrome This is often associated with renal disease, congenital scoliosis, Sprengel’s deformity, brain stem abnormalities, synkenesis, congenital heart disease and/or congenital cervical stenosis. It is characterised by multiple fused cervical segments due to the segmentation failure of cervical somites within the first eight weeks of gestation. In most cases the treatment is conservative but chronic pain may require surgery. Afflicted children should avoid aggressive sports. 2) Atlantoaxial Instability This is often associated with various osteochondrodystrophies, Down Syndrome, osodontoidium or other disorders. Rotatory Atlantoaxial Subluxation. [which is often caused by retropharyngeal inflammation] may manifest torticollis. If so this is best treated with traction and bracing, early. Traumatic Atlantoaxial Subluxation may also manifest torticollis which should be treated initially with a soft collar for up to a week. If symptoms persist, cervical traction may be required followed by fusion for fixed rotary subluxation. 3) Os Odontoideum This appears like a type II odontoid fracture. It may represent the residuals of a previous trauma but causes can’t be verified. If radiographs reveal instability of more than 3mm or neurologic symptoms present a posterior C1C2 fusion is required. 4) Pseudosubluxation of the Cervical Spine Similar symptoms to those involving pseudosubluxation are common in children over 8 because of the orientation of the facets. The more serious disorder can only be firmly diagnosed if: •
major trauma is evident
•
the subluxation with neck extension is reduced
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pain is resolved easily
•
the posterior spinolaminar line and the interspinous distances are mal aligned
•
there is anterior swelling.
5) Intervertebral Disc Calcification Syndrome This disorder is characterised by an increase in E.S.R. reading, low grade fevers, radiographic disc calcification without erosion, decreased R.O.M. and severe pain. The Cspine is most comTmonly involved. It is a selflimiting disorder and treatment is conservative. 6) Basilar Impression/Invagination This disorder is a bony deformity at the base of the skull which is characterised by paraesthesia [sometimes hydrocephalus] and weakness. It is caused by cephalad migration of the odontoid into the foramen magnum. Operative treatment is sometimes necessary and can include transoral resection of the dens, occipital laminectomy, also occipitocervica fusion and wiring.
Other Spinal Abnormalities These include:
•
Diastomatomyelia which is a longitudinal cleft in the spinal cord; either cartilaginus, fibrous or osseous bar. It can lead to tethering of the spinal cord with associated neurologic deficits. Sometimes it is necessary to resect